The documents distributed by this server have been provided by the
contributing authors as a means to ensure timely dissemination of
scholarly and technical work on a noncommercial basis. Copyright and all
rights therein are maintained by the authors or by other copyright
holders, notwithstanding that they have offered their works here
electronically. It is understood that all persons copying this
information will adhere to the terms and constraints invoked by each
author's copyright. These works may not be reposted without the explicit
permission of the copyright holder.